This invention relates to cleaning equipment used on land surfaces, and more particularly but not by way of limitation to apparatus for picking litter and other debris off sand beaches. Beaches attract fun-seekers and vacationers and, with them, disposable items which are left scattered on the shoreline, often embedded in the sand. The tides also bring in undesirable, unsightly flotsam and debris which, together with artificial trash, have to be picked up.
The major difficulty encountered in cleaning litter off beaches with machines is picking up the garbage without hauling off large volumes of sand and water. Several attempts have been made in the past to produce machines that can efficiently remove debris without removing sand. The present invention is a vast improvement over these previous attempts. For instance, U.S. Pat. No. 2,488,774 issued to Hassan discloses a beach cleaning machine which has excavating buckets mounted onto a rotating drum. The buckets are designed to scoop up large amounts of sand which are then sifted on an inclined screen. This design would be inefficient and time consuming in practical application since much of the effort will be directed to filtering bulk sand.
U.S. Pat. No. 2,744,739 issued to Evans et al. discloses a beach cleaning device which has the same basic design as Hassan '774, except for elongated blades which are mounted along the length of a rotating drum instead of excavating buckets. Both Hassan '774 and Evans '739 are designed to scoop large amounts of sand which is then filtered for litter and sand allowed to return to the beach. U.S. Pat. No. 2,733,904 issued to Gauther et al. discloses a beach cleaner which utilizes an adjustable shovel and a paddle wheel. The shovel is lowered onto sand and forward movement of the entire machine combined with help from the paddle wheel pushes sand into the shovel and onto a sieve net.
In sum, prior art discloses drums which are dragged along the sand in the same forward direction as the powered vehicle which mounts or tows the drum. Prior art designs focus on lifting large bulks of sand containing litter upward onto screens for subsequent straining.
The present invention discloses an apparatus which can actually pick litter off a sandy beach without having to scoop upward bulk sand, avoiding needless effort and delay. Thus, an object of the present invention is to efficiently clean litter off beaches with minimal sifting of sand. This is accomplished using unique projections and protrusions on a rotary drum that is independently powered to roll in the opposite direction as the moving apparatus. Another object of the present invention is to dig into the subsurface of sandy beaches to bring to surface debris that may be lodged in the sand. These and other improvements will become evident to those skilled in the art in the following disclosure.